Pin puller



Aug. 15, 1967 R. M. BARTON PIN FULLER Filed Feb. 14, 1966 4 Sheets-Sheet1 j7o7/67ZZ07 $587 5 MBqrZow Filed Feb. 14, 1966 g 1957 R. M. BARTON3,336,001

PIN FULLER 4 Sheets-Sheet 2 110 E 79PM 799 Aug. 15, 1967 R. M. BARTON333mm PIN FULLER Filed Feb. 14, 1966 4 Sheets-Sheet 3 Aug. 15, 1967 R,BARTON 3,336,0Q1

PIN FULLER Filed Feb. 14, 1966 4 Sheets-Sheet I I I J52 0672 Z19)"./?9Zer1 ff Bawim United States Patent 3,336,001 PIN PULLER Robert M.Barton, Normal, Ill. (Lincoln and North Sts., Towanda, Ill. 61776) FiledFeb. 14, 1966, Ser. No. 526,984 8 Claims. (Cl. 254-18) ABSTRACT OF THEDISCLOSURE The present invention relates generally to apparatus for theremoval of pins from forms, or the like, which have been driven into theground to hold the forms in place while concrete, for example, ispoured.

In particular, the present invention discloses an arrangement whereby apulling force is generated between an arm which is engaged throughappropriate means with the pin, and a pivoted reaction member adapted toengage and bear against the top of the form on either side of and to therear of the pin to be pulled. There is also provided on the reactionmember, auxiliary rams located outwardly, beyond the pin position, andon either side thereof. The rams are responsive to a pressure buildup inan actuator between the puller arm and reaction member which signalsresistance at the pin. The rams in response to the pressure buildupengage the form to provide a four-point stance about the pin to therebyfacilitate its removal.

In addition, a control is provided for regulating the fluid supply froma pump to the hydraulic members to permit either part or all of the pumpoutput to be employed at the actuator at the discretion of the operator.

The present invention pertains to apparatus for the mechanical rem-ovalof pins or the like from forms, and is directed to improvements in suchdevices providing high mobility and power.

With the advent of interstate expressway and highway systems, many ofwhich are poured concrete, there is an increased demand for equipmenthaving high mobility and efiiciency so as to reduce the length of time,as well as the amount of labor, involved in road construction. In roadconstruction where concrete is to be poured, whether it be for a citystreet or a highway, the road bed is laid out and forms, usually ofsteel, are positioned to define the limits of the road bed. Positioningof these forms is usually accomplished by driving pins or spikes throughan appropriate aperture in a form and into the hard soil basetherebeneath. After the concrete is poured and set, the forms areremoved by first removing the pins which hold the form. Due to numerousfactors, which include the length and size of the pin or spike, thecharacter of the soil base into which it has been driven, and thelateral pressures developed by the concrete on the form itself,extraction of these pins or spikes from the forms often requiresconsiderable power.

Devices are available for the removal of these pins by hand, applying alever principle, but a particularly tenacious pin might well requiremore effort, and at the very least, more time than practical, therebyrendering hand tools of this type ineflicient.

Other devices, some of which employ hydraulics or pneumatics to generateforce, for removing the pin, have been developed, but devices of thistype heretofore knownlack the necessarymobility and power, withinpractical limits, to meet the demands of present day road buildingtechniques.

It is an object of the present invention to provide an improved powerpin puller which is capable of great mobility and speed, and thusefficiency, in the removing of pins or spikes from forms or the like. I

It is another object of the invention to provide an improved powered pinpuller having highly efiicient reactive load distribution which permitsoptimum use of available forces for the removal of stubborn pins.

Still another object of the invention is to provide a pin puller of thecharacter herein described which is readily controlled and operated byone man, and by that man from one position adjacent the machine itself.

These and other objects and advantages of the invention will appear fromthe following detailed description taken in conjunction with thedrawings, wherein:

FIG. 1A is a perspective view of the forward pin pulling section of amachine constructed in accordance with the present invention;

FIG. 1B is a perspective view of the rear section of the device of FIG.1A;

FIG. 1C illustrates the manner in which FIGS. 1A and 1B may be placedside by side to permit the complete apparatus to be viewed;

FIG. 2 is a perspective of the device, viewed from the forward, pinpulling area, and illustrating the action of the device with respect tothe form and pin or spike to be removed;

FIG. 3 is a side elevation, partially sectioned, illustrating certaindetails of construction;

FIG. 4 is a schematic hydraulic layout of the control system; and

FIG. 5 is a detailed section of an auxiliary rain employed in the deviceof the present invention.

While the invention is susceptible of various modifications andalternative constructions, certain illustrative embodiments have beenshown in the drawings and will be described below in considerabledetail. It should be understood, however that there is no intention tolimit the invention to the specific form disclosed, but, on thecontrary, the intention is to cover all modifications, alternativeconstructions and equivalents falling within the spirit and scope of theinvention as expressed in the appended claims. The term pin or spikewill be used interchangeably in the following description, and shall bedeemed representative of those objects specifically described, as wellas similar or equivalent objects which might be readily extracted orremoved by a device of the type described within the spirit and scope ofthe invention. In a like manner, the term form shall be usedhereinafter, not only in its literal sense, but in a representativefashion as exemplary for purposes of illustrating the operation of theinvention without so limiting the same.

General mechanical arrangement invention, is there illustrated. Theapparatus comprising i the present invention is disposed on a suitableframe 12 which may be of tubular steel or beam construction, and theframe is rendered portable by means of wheels, at least some of whichare power driven. More particularly, a pair of rear wheels 14 (one shownin FIG. 1B) are provided, and mounted to the frame by a suitableL-shaped axle 16 which is welded or otherwise secured at an appropriateheight to the frame member 12. An identical wheel is disposed on thesame frame section at the right rear, although this Wheel, forconvenience, is not illustrated in this figure.

In order that the device may be guided by, and moved upon, the formsection F, a pair of flange Wheels 18 are supported for rotation onframe members 20 which are secured to the main frame portion 12 of thedevice. A cross plate 22, which spans the supporting frame members 20journals a .stub axle for support of the wheels 18.

Each wheel 18 is generally parallel with the wheel 14, and all of thewheels 14 and 18 are disposed to permit the movement of the device in adirection parallel with the length of the form F. Thus, the entirecarriage is movable along the form to a position for removal of pinstherefrom.

As will be seen in FIG. 1A, a gear 25 is secured in any convenientfashion to one of the wheels 18, and a chain 27 connects the gear with apinion 29. The pinion 29 is driven in either direction by a hydraulicmotor 31, of any suitable known construction. It will be appreciatedthat both wheels 18 might be driven, although in this illustrative case,only one such driving connection is specifically shown.

Puller assembly Disposed upon the frame 12 comprising the carriage ofthe unit, is the puller assembly which, in the illustrative case,comprises an upstanding post 40, disposed on a platform comprising apart of the framework at the rear of the unit itself. The height of thepost is a matter of design, and may conveniently be approximately fourfeet in height. At the top of the post, as illustrated in FIG. 3, apuller arm indicated generally at 42 is pivotally mounted about a pin44.

Referring to FIGS. 1A and 1B, the puller arm, as illustrated, comprisesa light but strong steel framework, including a pair of side framemembers 47 which fit into a clevis arrangement 50, the clevis memberbeing the member which actually engages the pin 44.

The side members are joined at the ends thereof remote from the pivotpoint by a cross plate 52. This plate, in the exemplary case, is formedwith a pair of holes 54 for receipt of a U-bolt 56 in which a chain 58is connected. It will be understood that the specific length of thechain may be readily varied by inserting the U-bolt 56 through any oneof the links. At the end of the chain a claw member C is disposed, forengagement with the enlarged heads of pins P (see particularly FIG. 2).The claw member works much in the same manner as the now familar tongsfor handling blocks of ice, in that, referring to FIG. 2, upward pull onthe chain results in the closing of the claws about the pin in grippingrelation. The claw is vertically aligned with each pin by simply movingthe entire carriage on the form to a position above the pin to bepulled.

In the illustrative case, power is supplied to the puller arm by meansof a fluid motor, exemplified by the cylinder 63 having a reciprocablerod 65 emanating therefrom. In order to support the cylinder and rodarrangement and provide a suitable stroke, an upstanding frame isprovided on the puller arm, and comprises a pair of pillars 67 welded orotherwise fastened to the side members 47 at a posiiton rearwardly ofthe plate 52. The pillars 67 are joined by a cap 69, and the end of therod 65 is threaded into a T-pipe 72. The pipe is pivotally secured tothe upstanding frame by means of a pivot pin 75 passing therethrough andfitted into the pllars 67 at a suitable spot near the top of thepillars.

In order, in keeping with the invention, to distribute the reactionforces developed during removal of a pin, directly on the form F aboutthe pin rather than on the frame or carriage 12, which would require theframe to be much heavier than it is, a reaction arm. indicated generallyat 80 (see FIG. 3) is provided, The reaction arm, like the puller arm,is conveniently pivotally mounted to the rear upstanding post 40 bymeans of a pin 82 disposed near the base thereof. The reaction armcomprises an elongated central frame member 85 which is disposed ingenerally vertical alignment with the puller arm, and which terminatesin a centrally disposed cross member 87. A pair of lugs 89 are welded orotherwise suitably secured to the top of the member 85, and both aredrilled to receive a pivot pin 91 which connects with the base of thepower cylinder 63 by passing through link 92 for a limited pivotalmovement thereof about the pin 91. The cross member 87 is provided withlateral support by oblique frame members 95 which extend from the endsof the cross member 87 rearwardly to a convenient spot on the arm 85where they are secured in any suitable fashion. The construction lendsconsiderable strength to the cross member which will, as now will bedescribed, absorb a substantial amount of the forces generated by thepuller.

Referring to FIG. 2., a pair of legs depend from the cross member 87near the respective ends thereof. The legs are of sufficient length topermit engagement with the top of the form F with the central reactionframe member 85 disposed at a predetermined height above the main frame12 of the unit. Upon application of power to the fluid motor 63, the rod65 extends acting between the arms 42 and 80. With the claw engaged, thearm 42 is momentarily held and the force generated by the motor 63 willurge the arm 80 downward about pivot pin 82 until the legs 100 engagethe form. Once this happens, all forces are between the form and thepin, with the result that the pin is extracted. The position of the legs100 permit a balanced distribution of the reaction forces on the form,thereby permitting optimum pulling power.

In order to absorb some of the shock resulting from the freeing of thepin P upon application of substantial force by the fluid motor, shockabsorbing spring have been provided between the central arm 85 and anarch indicated generally at 107 disposed on a frame member 12 andextending upwardly for a suitable distance above the arm 85. The springsare arranged to minimize recoil of the device when the pin P is freed.

The control system Experience has demonstrated, that in a device of thistype, fluid power is both efiicient and economical. While the potentialof other modes of powering and controlling the apparatus of the presentinvention are recognized, an exemplary hydraulic power control systemwill be described for purposes of demonstrating the convenience andversatility of the operation of the machine itself. A schematichydraulic layout is illustrated in FIG. 4, and will be referred to inconjunction with the figures illustrating the mechanical construction ofthe device to explain the operation thereof.

A gasoline engine E is provided which is connected directly to a doubleor two-sided hydraulic pump 110 of known construction. An oil reservoirR is shown, and may be located at any convenient position on the frame12. Fluid is tapped from one side of the pump 110 through line 112 tothe input of the drive motor control valve 115. The control valve 115supplies fluid to drive motor 3-1 through a forward line 117 and areverse line 119 for selective directional rotation of the drive motor,and resultant movement of the entire device along the form F.

Input pressure is likewise fed through line 122 to the lift controlvalve 125 which selectively directs fluid through line 127 to extend therod 65, and through line 129 to retract the rod 65. It will beappreciated that, in the case of the control valve 115 and the controlvalve 125, switching of pressure from one line to the otherautomatically connects the line previously under pressure with thereservoir in any known manner to permit exhaustion of fluid on thatparticular side of the device being operated. It will also beappreciated that the specific construction of the valves herein employedis well known, and for that reason, the internal workings thereof havenot been illustrated. It is believed, however, that from the schematicdiagram presented, the system as it applies to the present invention, isreadily understood.

It is an additional feature of the present invention that availablefluid pressure at the control valves may be selectively increased toprovide additional power for transporting the device or extracting aparticularly stubborn pin. To this end, and referring to FIG. 4particularly, a two position fluid regulator valve is provided which isconnected by line 137 to the other side of the pump 110,

and which is selectively operable to (a) direct fluid in line 137directly to input line 112, by means of a line 139, or (b), bypass thesame to the reservoir through line 141. Thus, a half power and fullpower position is provided at the instance of the operator.

Auxiliary'apparatus for distribution reaction force In keeping with theobjective of producing a maximum amount of vertical pulling force at thepin P with a light weight structure having maximum ability, theinvention provides auxiliary apparatus which automatically redistributesthe reactive load on the reaction arm 80' when the pressure applied tothe fluid motor 63 exceeds a predetermined amount. More particularly,means is provided for redistributing the reactive force on a four pointstance, evenly positioned above the pin to be pulled as contrasted tothe two point stance provided by the legs 100.

Referring to FIGS. 1A and 3 in particular, a pair of auxiliary ramsindicated generally at 150 are provided in a position in a generalalignment with each of the legs 100 and outwardly thereof to a positionbeyond the normal position of the pin P in the form, so as to place thepin within an imaginary box defined by the intersection of linesconnecting the adjacent ones of legs 100 and rams 150.

In order to support the rams, a pair of side plates 153 extend outwardlyfrom the cross member 87 where they are secured, as well as along thelegs 100* by any known method such as welding. Each pair of plates 153is supplied with positioning apertures -5 disposed in alignment andadapted to receive a pivot pin 157 which anchors the cylinder portion159 of the ram 150 to the plates while permitting limited movement aboutthe pin.

Referring to FIG. 5, the internal structure of the ram is illustrated ascomprising a piston rod 161 which extends from the cylinder 159 and isprovided at its lower end with the abutting foot 163 for engagement witha portion of the form F. The other end of the rod is provided with apiston 165 which is disposed below a port 167 which opens into a chamber169 defined between the end of the cylinder and head of the piston 165.A heavy compression spring 171 is seated behind the piston 165 andextends the length of the cylinder 159 to engage the piston behind thehead 173 thereof.

Referring to FIG. 4, the port 167 connects to fluid line 127 by means ofa tap- 175. Fluid line 177 extends from the tap to the port 167 topermit fluid to enter the chamber 169. Thus, when the valve 125 is in aposition to permit fluid to flow into line 127 for extending the rod 65(pulling force being generated), fluid is likewise transmitted throughline 177 to the auxiliary ram chamber 169. When the pressure in thechamber 169 acting against the piston 175 is s-uflicient to overcome theforce of the spring 171, the rod 161 is extended and the foot 163-engages the form. As a consequence, the reaction arm assumes a fourpoint stance about the pin. This brings about a distribution of reactiveforces which permits even the most stubborn pin to be removed withrelative ease by the device. When pressure is relieved in line 127 byreversal of the valve, line 177 is likewise bled and the ram returned bythe heavy spring 171. This device, with one man operating it, can pullpins over 2,000 feet per hour.

Transportation one of which is shown in FIG. 1B. The transport wheelsare disposed on either side of the device in an up on position duringactual use, but are capable of being extended to a position where theysecure the entire device on a two point stance on the wheels fortransportation. In accomplishing this, the wheels are mounted by meansof an axle 182 on a link 184 which is manipulated by a fluid motor 186.The fluid motor 186 is operated by a control valve 188 disposed, forconvenience, at the rear of the device. Valve 188 connects to a fluidsupply line through valve 125 by means of line 190, and pressure issupplied to either side of the fluid motor, which is of knownconstruction, by means of lines 192 and 194. Thus, upon completion of aparticular job, the pin puller is raised onto the transport wheels byapplying appropriate pressure to lowerthe wheels to the ground, whichwill result in the raising of the device. From that position, the entireapparatus may be connected to the bumper of a car or truck by a trailerhitch of known construction and transported to the next job.

On the basis of the foregoing description, and observing in FIG. 1A and2, that the placement of the valves 135, and is such that they are allwithin the easy reach of an operator who, from the same position, canalso operate the claw C, it is apparent that the apparatus in questioncan be manipulated very quickly to remove a pin, and thereaftertransport it to the next pin with great speed. One such exemplary devicedevelops the pulling of 20,000 pounds at the pin with a 10 horsepowergasoline engine, and a double pump developing seven gallons per minuteon each side.

I claim as my invention:

1. Apparatus for removing pins from forms or the like comprising aportable carriage having an upstanding post mounted thereon, a pullerarm pivotally mounted to said post and located above the pin to bepulled, a reaction arm disposed in vertical alignment with said pullerarm and pivotally mounted to said post, an actuator disposed betweensaid puller arm and said reaction arm, means depending from said pullerarm for engaging a pin, said reaction arm having abutments thereon forengagement with the form about the pin, on either side thereof, a fluidpump connected with said actuator and adapted to supply fluid underpressure thereto to thereby force said abutments against the form andurge said puller arm in a direction to pull the pin from the form, fluidpowered auxiliary rams mounted to said reaction arm outwardly of saidabutments, said rams being in fluid connection with said actuator andresponsive to pressure thereat, said rams being extensible to engage theform outwardly of said abutments upon application of a predeterminedfluid pressure thereto.

2. The apparatus as set forth in claim 1 wherein a control valve isdisposed between said fluid pump and said actuator for selectivelydirecting a portion of the fluid delivery of said pump thereto.

3. The apparatus as set forth in claim 2 wherein said auxiliary rams aremounted for limited pivotal movement with respect to said reaction arm,so as to apply pressure in a direction generally parallel with thepulling force on the pin.

4. The apparatus as set forth in claim 2 wherein each said auxiliary ramcomprises a cylinder having a chamber therein, a piston disposed in saidchamber and having a rod connected to said piston, said rod beingextensible from said cylinder to engage the form, said piston beingpreloaded so as to maintain said rod in a normally retracted position,said auxiliary rams and said actuator being fluidly interconnected sothat when the pressure supplied to said actuator from said control valveexceeds the pre-load on said piston, said piston is actuated to extendsaid rod.

5. The apparatus as set forth in claim 4 wherein an auxiliary controlvalve is provided between said pump and said control valve so as toselectively increase the fluid to said control valve to a value equal tothe total delivery of said pump.

6. The apparatus as set forth in claim 4 wherein said auxiliary rams areso positioned with respect to said abutment that, when extended,imaginary lines intersecting adjacent ones of said abutments and ramsdescribe a rectangle with a pin adapted to be disposed at theapproximate center thereof.

7. The apparatus as set forth in claim 4, including a pair of flangedwheels on said carriage in engagement with the form, and a motorconnected with one of said flanged wheels for rotating the same, andwheels opposite said flanged wheels on said carriage for supporting saidcarriage for movement in the general direction of the form.

8. The apparatus as set forth in claim 7 wherein a pair of retractabletransport wheels are provided on said carriage, and means for extendingthe same to a amount sufficient to fully support said carriage on saidwheels for transporting the apparatus.

References Cited UNITED STATES PATENTS 1,893,719 1/1933 Talboys 254182,271,311 1/1942 Shambaugh 254-18 X 2,911,190 11/1959 Creason 254183,063,676 11/1962 Robinson 254-30 X 3,249,334 5/1966 Sheperd et al.254-48 3,276,743 10/1966 Hahn et al. 25418 WILLIAM FELDMAN, PrimaryExaminer.

transport position wherein said carriage is raised an 15 MILTON S. MEHR,Examiner.

1. APPARATUS FOR REMOVING PINS FROM FORMS OR THE LIKE COMPRISING APORTABLE CARRIAGE HAVING AN UPSTANDING POST MOUNTED THEREON, A PULLERARM PIVOTALLY MOUNTED TO SAID POST AND LOCATED ABOVE THE PIN TO BEPULLED, A REACTION ARM DISPOSED IN VERTICAL ALIGNEMENT WITH SAID PULLERARM AND PIVOTALLY MOUNTED TO SAID POST, AN ACTUATOR DISPOSED BETWEENSAID PULLER ARM AND SAID REACTION ARM, MEANS DEPENDING FROM SAID PULLERARM FOR ENGAGING A PIN, SAID REACTION ARM HAVING ABUTMENTS THEREON FORENGAGEMENT WITH THE FORM ABOUT THE PIN, ON EITHER SIDE THEREOF, A FLUIDPUMP CONNECTED WITH SAID ACTUATOR AND ADAPTED TO SUPPLY FLUID UNDERPRESSURE THERETO TO THEREBY FORCE SAID ABUTMENTS AGAINST THE FORM ANDURGE SAID PULLER ARM IN A DIRECTION TO PULL THE PIN FROM THE FORM, FLUIDPOWERED AUXILIARY RAMS MOUNTED TO SAID REACTION ARM OUTWARDLY OF SAIDABUTMENTS, SAID RAMS BEING IN FLUID CONNECTION WITH SAID ACTUATOR ANDRESPONSIVE TO PRESSURE THEREAT, SAID RAMS BEING EXTENSIBLE TO ENGAGE THEFROM OUTWARDLY OF SAID ABUTMENTS UPON APPLICATION OF A PREDETERMINEDFLUID PRESSURE THERETO.